(a) Field of the Invention
The present invention relates to braking means and more particularly to improvements in a braking mechanism adapted to focal plane shutters.
(B) Description of the Prior Art
Generally, in a photographic shutter, shutter blades are stopped instantaneously after moving at a very high speed. Therefore, if the shutter blades and their actuating members are stopped by making them collide with a fixed stopper or the like, respective parts of the mechanism will be vibrated with a loud impact sound by the shock of the collision to cause a camera-shake, the actuating part will bound, the shutter blades will flex to cause a faulty exposure and the durability of the shutter will reduce as pointed out in various shutters and particularly in so-called metallic focal plane shutters having metallic shutter blades.
There has been already made a shutter in which a brake mechanism braking shutter blade or their actuating members is incorported to remedy the above mentioned defects. It is of a system of applying a friction brake to the shutter blades and their actuating member before they reach stopping positions. However, as the friction force is so made as to act on the actuating mechanism at the beginning even in the case of cocking the shutter, the load for cocking will be large and will greatly fluctuate at the beginning and end of cocking as disadvantages.